The thrill of City life appears to be fading for hundreds of investment bankers who are preparing to turn their back on the financial sector and opt for a career in science teaching.

The Training and Development Agency for Schools (TDA) has revealed that inquiries about science teaching posts rose by a third last September compared with the same month in 2007. The agency will reveal this week that formal applications for science teaching posts have reached record levels and that further significant rises are expected next year in the wake of the world financial crisis. Many of those applicants are coming from the City, it says.

Among those swapping the trading floor for the school laboratory is Elizabeth Baldwin. The 44-year-old worked for almost 20 years for major banks, including Merrill Lynch and Lehman Brothers, until she found, a few months ago, that the excitement of the job was disappearing.

'I had just had my second child, Thomas, and the thought of going back to the City became less and less palatable,' she said. 'The high pay no longer compensated for the long hours and lack of social life.'

So the business analyst - who has a degree in chemistry and biology from King's College London - quit and is now applying to join a training course to become a science teacher. The City is a major employer of science graduates. As it cuts back on jobs, and as more individuals like Baldwin become disillusioned with the financial sector, the numbers of science teachers are set to soar as stockbrokers and analysts quit their Ferraris and stock options for test tubes and Bunsen burners, according to experts.

'There is no doubt that the credit crunch has a huge silver lining in terms of science education in Britain,' said Graham Holley, the agency's chief executive. 'It is going to do a great deal of good for the teaching of chemistry, physics and biology.'

Science teaching has been a cause of considerable concern for education experts for decades. The City has attracted large numbers who are employed, often with lucrative salaries, as business analysts and IT experts. As a result, fewer graduates with top degrees have become teachers. Physics, chemistry, biology and mathematics classes have suffered and fewer children have been inspired to take up science.

In turn, fewer graduates has meant fewer scientifically trained individuals available to work for British industry - and not enough good graduates available to become teachers, who are needed to inspire future generations of sixth-form students and undergraduates to study science subjects.

The government pledged years ago to halt this trend and has introduced a number of measures, including increased salaries for science teachers compared with those in other subjects.

The TDA also launched its Transition to Teaching programme this year to increase numbers. Encouraging results are emerging. This week the agency - which is responsible for boosting teacher recruitment in Britain - will reveal that for the first time the country has exceeded the target set for numbers of new science teachers.

A total of 3,114 science trainees entered colleges during the academic year 2008-09, a rise of 2.5 per cent on the previous year. 'That is the highest number of science teachers we have recruited since the TDA began 13 years ago,' said Holley.

Most of these new recruits have been encouraged by schemes that ensure that salaries start at around £24,000 for science teachers, and can eventually rise to £50,000 for more mature candidates, according to the TDA.

It is a reasonable reward, but it certainly does not match what a science graduate can earn in the City, a point stressed by Baldwin.

'I will be earning a third of what I would have got had I stayed in the City,' she said. 'But money is not everything. Instead of going to work early and leaving very late, I will get a chance to come home and be with my boys, Matthew and Thomas.

'My father was a teacher, so I know what to expect and what I will get out of the job. I know teaching won't be easy, but I know as well that it can be very rewarding.'

'I wanted more time with my boys'

For two decades, Elizabeth Baldwin worked for major banks including Lehman Brothers and Bank of America - a job that took her to Australia, Hong Kong and London.

'The City was part of my life. I would work long hours and then drink with friends. It was in my blood, though it did mean that I never saw my house in daylight.

'But after the birth of my sons - Matthew, who is two-and-a-half, and Thomas, who is 15 months - I found the place was no longer my natural habitat.

'Each time I went back after maternity leave, it no longer felt familiar or safe. So I decided to find a job that would give me some time with my boys.

'My father was a teacher and my sister is a teacher, so it was natural that I would think of education. I am not jumping into it, however. My salary will be about a third of its previous level, although my partner still has his job in the City.

'I will miss the cut and thrust, and the gossip. On the other hand, it will be good to get home by 5.30 and see my children.'